Prior art track lighting systems comprise elongated power tracks that are mountable to a ceiling or other interior surface of a building. The power tracks include a longitudinally extending channel on the side thereof facing away from the ceiling or other such mounting surface in the building. Disposed within the channel are one or more pairs of parallel conductors that are electrically connected to the electrical power lines of the building at a junction boxes or the like disposed in the ceiling.
Prior art track lighting systems further include at least one, and generally a plurality of track lighting units that are electrically and mechanically engageable in the channel of the power track mounted to the ceiling or other such mounting surface in the building. More particularly, the track lighting units include a base having a pair of electrical contacts mounted thereto. The portion of the base to which the contacts are mounted is dimensioned to be urged into the channel of the power track. Additionally, the base includes appropriate means for selectively moving the contacts thereof into electrical engagement with the elongated conductors of the power track. The contacts of the base are electrically connected to a light socket in the track lighting unit. Thus, the light socket can be selectively placed in electrical connection with the elongated conductors of the power track.
The outlet or junction box to which the power track is connected generally is operatively controlled by a switch disposed in a wall or other convenient location that is spaced from the power track. The switch is operative to complete a circuit, thereby directing current to the power track and enabling the simultaneous lighting of the bulbs of all track lighting units mounted to the power track of the system. The switch may include known dimming means to enable the simultaneous and uniform dimming or brightening of all track lighting units mounted to the power track.
The above described track lighting systems are used in a wide range of residential, office, commercial and institutional applications where it is desirable to illuminate specific locations in addition to illuminating an entire room. Thus, track lighting systems are widely employed in museums and art galleries where specific wall hangings are to illuminated and accented. Similarly, track lighting systems are employed to emphasize commercial displays in retail establishments, architectural displays in office buildings, specific tables in a restaurant and various other items of interest or importance in virtually any building. Among the desirable features of track lighting systems is the ability to move the various track lighting units longitudinally relative to the power track as lighting needs change. For example, lighting requirements may vary as commercial displays are changed, as furniture is rearranged or as new art gallery exhibits open.
In addition to changing the locations of track lighting units, it is often desirable to provide more or less illumination in certain areas as compared to other areas. With prior art track lighting systems, this can be accomplished by selectively adding or removing track light units to the power track or by changing bulbs in individual track lighting units to a smaller or larger wattage. This approach can be extremely time consuming and awkward. In this regard, it is to be understood that the ceilings in many commercial, office, industrial or institutional buildings are quite high, and the power tracks mounted thereto are not easily accessible. Furthermore, it may often be necessary to experiment with the various lighting options to achieve a desired effect.
Some prior art track lighting systems include a power track having plural circuits (typically up to five circuits) which are separately controllable. Thus, one track lighting unit in a power track may be disposed on one circuit, while the track lighting unit adjacent thereto is disposed on a separate circuit on the same power track. Multi-circuit track lighting systems are very significantly more expensive than single-circuit track lighting systems. Additionally, multi-circuit track lighting systems require multiple circuit wiring to be incorporated into the building in which the track lighting system is installed. In most situations, the plural circuits are not pre-existing in the building, and costly electrical work must be completed before the expensive multiple circuit track lighting system can be installed. This electrical work will require the installation of separate controls for each circuit in the power track. Even when such a system is installed, it is likely that the arrangement of circuits will not conform to each lighting need. As a result, it will be necessary to periodically make direct adjustments to the track lighting units. Furthermore, limitations as to the possible number of circuits that can be incorporated into the track will constrain the system. Five circuits defines a practical limit for even the most complicated and costly multi-circuit track lighting system.
As noted above, the multiple circuit track lighting systems are significantly more expensive than single circuit track lighting systems. These cost differentials can increase dramatically as the size of the room or building increases. In particular, the circuitry required for large art galleries, exhibition halls, conference rooms, and large commercial spaces can be extraordinarily expensive. Examples of complex expensive lighting systems for separately controlling individual lighting units are shown in: U.S. Pat. No. 4,792,731 which issued to Pearlman et al. on Dec. 20, 1988; U.S. Pat. No. 4,689,547 which issued to Rowen et al. on Aug. 25, 1987; U.S. Pat. No. 4,733,138 which issued to Pearlman et al. on Mar. 22, 1988; U.S. Pat. No. 4,388,566 which issued to Bedard et al. on June 14, 1983; U.S. Pat. No. 4,242,614 which issued to Varis et al. on Dec. 30, 1980; and, U.S. Pat. No. 4,057,751 which issued to Bonsignore et al. on Nov. 8, 1977.
Prior art not relating to track lighting systems includes electrical signal transmitting and receiving devices that rely upon electrical power circuits of a building for transmitting signals. For example, prior art devices of this type are manufactured by the X-10 Corporation which include receivers having a plug for insertion into a standard wall outlet and a socket for receiving a standard lighting fixture plug. The receivers include signal responsive switch means which is operatively connected to the plug of the receiver and which controls the current flow to the socket of the receiver. The signal responsive switch means of this prior art receiver typically includes an address which is one of 256 selectable addresses. The switch means responds only to signals directed to the address selected for its receiver. These prior art receivers are used in combination with prior art transmitters. The transmitters also are plugged into standard wall outlets and are operative to generate signals that are transmitted through the electrical power circuitry of the building. More particularly, the transmitter is operative to generate a first signal which identifies at least one specific receiver address and a subsequent signal for identifying a particular switching function to be carried out by the receivers at that address. The prior art transmitters and receivers cooperate with one another to enable remote control of different outlets. For example, the prior art receiver will effectively "hear" its address being signalled by the transmitter, and will adjust the switch means disposed therein in response to the next signal generated by the transmitter. An alternative of the above described prior art system incorporates the receiver into a standard wall-mounted electrical switch. This prior art receiver will perform the same functions as the above described receiver which is pluggable into an outlet. However, these prior art signal systems have generally been adapted for incorporation directly into a single wall outlet either in the form of a switch or a socket. These prior art power line signal responsive switching systems have not been developed for controlling a plurality of different lighting units extending from a single junction box or wall outlet, and particularly have not been adapted for use with track lighting systems.
In view of the above, it is an object of the subject invention to provide a single circuit track lighting system with each light thereon being separately controllable.
It is another object of the subject invention to provide a track lighting system for incorporation into a power line signal carrying switch system which may include components of existing signal systems and which further may include: computers, sensors and alarm systems.
A further object of the subject invention is to provide power line signal responsive switch assemblies incorporated into individual track lighting units of a track lighting system.
Yet another object of the subject invention is to provide power line signal responsive switching adapters selectively engageable with a power track of a prior art track lighting system and mateable to a prior art track lighting unit.
Still an additional object of the subject invention is to provide a power line signal responsive switching unit that can be incorporated into a track lighting system without significantly altering the aesthetic appearance of the track lighting system.
An additional object of the subject invention is to provide a remote control system that is compatible with and can coexist with any available track lighting system.